Method and apparatus for the continuous manufacture of a compound pipe with a pipe socket

ABSTRACT

For the continuous production of a composite pipe comprising a smooth inner pipe (107) and an outer pipe (105) which is provided with transverse grooves (24) and welded to said inner pipe (107), the said composite pipe having a pipe socket, an outer flexible tube (104) is extruded and an inner flexible tube (106) extruded into this. During the production of the normal composite pipe, gas is blown at a slight superatmospheric pressure into the region between the outer flexible tube (104) and inner flexible tube (106). During the production of the pipe socket, this region is vented to achieve full-surface contact of the inner flexible tube (106) against the outer flexible tube (104), for which purpose the inner flexible tube (106) is pressurized with gas from its inside. &lt;IMAGE&gt;



